1. Field of the Invention
The invention relates to a mobile communication system, and more particularly, to a method of transmitting packet data in a communication system.
2. Discussion of the Related Art
The existing mobile communication systems often use physical channels such as one or more Packet Data Channels (PDCH) and Packet Data Control Channels (PDCCH) for transmitting packet data. A PDCH is a channel through which one or more packet data sets are transmitted to one or more mobile stations (or users). Each mobile station may share a PDCH with others by using a Time Division Multiplexing (TDM). The PDCCH is a control channel through which one or more control signals are transmitted. A control signal contains control information that enables one or more mobile stations to receive a data packet through a corresponding PDCH.
In current systems, a base station transmits packet data sets to mobile stations by using a TDM. The packet data sets can be transmitted to each mobile station in different time intervals or can be transmitted in a same time interval by using different codes (e.g., Walsh codes) that identifies a packet data set for each mobile station.
The packet data set being transmitted to each mobile station by using a TDM method always uses all the resources available in a PDCH, even if it is not necessary for all the communication resources to be exhausted. Consequently, the system resources are often wasted. In addition, in existing systems that use a TDM method, the period of time for transmitting a packet data set to each mobile station through a PDCH is fixed. Therefore, it is very difficult to use the system resources efficiently. A data communication method is needed that can overcome the above-referenced shortcomings by more efficiently utilizing the transmission resources of the communication system.